No, only spiders eat their own webs, and only to recycle them. Humans have used spider silk for many things, including rituals, gun scopes and even fish nets, but I have never read anything about them being a viable food source. read more
So you'd get a small amount of sustenance but nothing major, you'd benefit more from eating the spider itself probably. However there's a difference between edible and palpable palatable. Tree bark is edible but not palpable meaning it probably isn't enjoyable to eat. read more